25th April 2012 - When it comes to the health benefits of eating chocolate, dark, not white chocolate, is the clear winner according to new research.
"Eat dark chocolate, not white chocolate," says researcher Mee Young Hong, PhD, associate professor of exercise and nutritional sciences at San Diego State University in the US. She compared dark and white chocolate, looking at health effects, such as improving cholesterol.
Cocoa solids contain healthy compounds called flavonols which have antioxidant and anti-inflammatory properties.
Professor Hong compared white chocolate, which has no cocoa solids, to regular dark chocolate containing 70% cocoa. She also tested dark chocolate containing 70% cocoa that had been overheated or ''bloomed" (melted and then maybe hardened again) to see if the melting would rob the dark chocolate of the health effects.
In the name of science Professor Hong's team assigned 31 men and women to eat about 1.7 ounces (50g) of dark, white, or ''bloomed" dark chocolate every day for 15 days. Their blood pressure, blood sugar, and cholesterol were measured before and after the study.
Compared to those who ate white chocolate, those eating either dark chocolate had:
Lower blood sugar levels
Improved LDL or 'bad' cholesterol
Improved HDL or 'good' cholesterol
Those who ate dark chocolate lowered their bad cholesterol by about 20%, Professor Hong tells us. Dark chocolate eaters increased their good cholesterol by 20%, compared to white chocolate eaters.
As for why the dark chocolate may help blood sugar levels, Professor Hong says its antioxidants may help the body use its insulin more efficiently to control blood sugar. This, in turn, helps to lower blood sugar levels naturally.
The white chocolate, but not the dark, made the skin blood flow slow down - not a desirable quality. Skin blood flow is a way to measure how the blood vessels are functioning.
Professor Hong didn't find differences in blood pressure between the white chocolate eaters and the dark chocolate eaters.
Chocolate for health: Perspectives
Some of the findings echo those of other research, says Joe Vinson, PhD, a professor of chemistry at the University of Scranton US and a long-time researcher on antioxidants in foods. He reviewed the findings.
"The fact that white chocolate (containing fat and sugar) makes the skin blood flow slow down is newsworthy," he says. The message to stay healthy, he says, is: "Don't eat fat and sugar without antioxidants."
The finding about bloomed chocolate is reassuring if you're wondering whether to eat old chocolate, Professor Vinson says. It may look bad but it still has active antioxidants.
Other studies, but not this one, have found lowering of blood pressure with dark chocolate. Eric Ding, PhD, a nutritional epidemiologist and instructor of medicine at Harvard Medical School US says.he fact that Professor Hong did not could simply be because of the small size of the study.
"The LDL decrease and the HDL increase are consistent with previous research," Eric Ding tells us.
The blood sugar finding is newer, he says.
Professor Hong reminds chocolate lovers that moderation is key.
These findings were presented at a medical conference. They should be considered preliminary as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.
The study did not have industry funding.
Experimental Biology 2012, San Diego, April 21-25, 2012.
Mee Young Hong, PhD, associate professor of exercise and nutritional sciences, San Diego State University.
Joe Vinson, PhD, professor of chemistry, University of Scranton, Scranton, Pa.
Eric Ding, PhD, nutritional epidemiologist and instructor of medicine, Harvard Medical School, Boston.
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